1. Field of the Invention
The present invention relates to a method, system, and program to provide property value information for a device.
2. Description of the Related Art
The Web-Based Enterprise Management (WBEM) framework is a set of management and Internet standard technologies developed to provide a common set of protocols to enable the management of enterprise computing environments. The WBEM standard includes the Common Information Model (CIM), which provides a conceptual framework for interchanging information between management systems and applications. The CIM schema provides a set of object oriented classes with properties that are used to organize and access the information about the managed environment in a common format. The WBEM/CIM schema allows one to use a web browser to access a CIM compliant server to access information from a device using the CIM framework. One can construct a generalized management application using the CIM framework and components without needing to know or incorporate device specific or proprietary commands of the device being managed.
The elements that may be managed and accessed using the WBEM/CIM framework include systems, applications, networks, and devices (e.g., storage systems, printers, etc). Extension schemas are provided to extend the CIM to technology-specific areas, such as storage devices. To comply with the CIM architecture, a product must implement the CIM core and common schema classes to enable CIM clients to use standard CIM methods to access information about the product. This requires the product vendor to develop product (e.g., application, device, system, etc.) specific code that implements the CIM classes to provide access to the product information.
The CIM model provides a core model that captures notions applicable to all areas of information management. A common model provides access to information common to particular management areas, but independent of a particular technology. Extension schemas represent technology specific implementations of the model that provide access to information specific to a particular product. Vendors must, thus, provide an instance of the model to enable access to the product information and configuration settings as specified in the CIM specification. Further details of the CIM model are described in publications from the Distributed Management Task Force (DMTF), including “Common Information Model (CIM) Specification”, Version 2.2, (Jul. 14, 1999) and “Understanding the Application Management Model”, Version 1.0 (May 17, 1998), which publications are incorporated herein by reference in their entirety.
The CIM indication schema provides classes used to communicate occurrences of events in the managed environment. An event is typically assumed to be a change in the state of the device environment or a record of the behavior of some component of the environment. Examples of events include the starting or stopping of a service, addition of resources to a monitored device, the occurrence of a pervasive incident, state change requiring immediate attention, such as being low on disk space, etc. The occurrence of an event is represented by an instance of the CIM Indication class. Clients can subscribe to indications caused by changes in the state of CIM objects to receive notification and alerts when certain states or information changes in a managed object. Subscription refers to the classes and methods that clients use to subscribe to and receive indications. Details of the classes of the CIM indication schema are described in the DMTF publication “Common Information Model (CIM) Indications”, Version 2.5 (Dec. 14, 2000), which publication is incorporated herein by reference in its entirety.
As with the CIM model, vendors wanting to provide information on their products through the CIM indication schema, must implement the classes specified in the CIM model and CIM indications. This requires each vendor to write device specific code that in response to calls from methods defined in the CIM specification performs device specific operations to provide the requested indications and other information, and provide access to the device as defined in the CIM specification. This process of writing the device specific code to implement the classes of the CIM model and CIM indication is a substantially time consuming and expensive process.
Moreover, when network devices implement the WBEM/CIM framework, they may receive numerous requests for information from applications and browsers requesting information or performing management operations with respect to the managed device. Such devices, as storage systems, etc., are often not designed to function as a web server. Thus, devices that participate in the WBEM/CIM environment may experience a substantial increase in processing burdens due to the need to function as a web server and respond to information requests and control operations from external devices.
For these reasons, there is a need in the art to provide improved techniques to enable vendors to integrate their products into the CIM environment and provide property value information from the devices.